Calculate distance between two points in google maps V3

Question

How do you calculate the distance between two markers in Google maps V3? (Similar to the distanceFrom function inV2.)

Thanks..

Answer 1

Here is the c# implementation of the this forumula

 public class DistanceAlgorithm
{
    const double PIx = 3.141592653589793;
    const double RADIO = 6378.16;

    /// 

    /// This class cannot be instantiated.
    /// 
    private DistanceAlgorithm() { }

    /// 

    /// Convert degrees to Radians
    /// 
    /// Degrees
    /// The equivalent in radians
    public static double Radians(double x)
    {
        return x * PIx / 180;
    }

    /// 

    /// Calculate the distance between two places.
    /// 
    /// 
    /// 
    /// 
    /// 
    /// 
    public static double DistanceBetweenPlaces(
        double lon1,
        double lat1,
        double lon2,
        double lat2)
    {
        double dlon =  Radians(lon2 - lon1);
        double dlat =  Radians(lat2 - lat1);

        double a = (Math.Sin(dlat / 2) * Math.Sin(dlat / 2)) + Math.Cos(Radians(lat1)) * Math.Cos(Radians(lat2)) * (Math.Sin(dlon / 2) * Math.Sin(dlon / 2));
        double angle = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a));
        return (angle * RADIO) * 0.62137;//distance in miles
    }

}